difference for each attribute between the value indicated in the proposer
proposal and that in the reviewer counter-proposal.
Let R i [ k 0 1] be the rank of the attribute i in the last proposal formulated
by the reviewer and R i [ k ] the rank of the attribute i in the proposal received
from the proposer. The negotiator selects the attribute i where:
R i [ k
R i [ k ]
R j [ k
R j [ k ])
Equation 20.2 Selection of the attribute to change
The counter proposal has all the attributes equal to the last proposal
formulated but the selected attribute. For this attribute the counter-proposal
will have the value that has a rank immediately lower than the previous one.
If there exists more than one user interested in booking the same
resource, the negotiation processes can interfere with each other and
produce different results based on the duration of each negotiation process
and the number of concurrent negotiators. In the case of scarce resources,
the negotiators might be competitors: only one will conclude the negotiation
process and get the service.
The negotiation process might last hours or days. Each contractor can set
the period of time that must separate two negotiation steps, that is how long
the proposer wants to wait before submitting a counter-proposal to the
reviewer. An anxious proposer will try to get the service by formulating
proposals that accommodate the reviewer's counter-proposal as fast as
The laboratory reservation system must exhibit the following features:
Problem representation . The problem that is the object of negotiation
must be represented in terms of attributes and their possible values.
Negotiation . Based on the problem description it is possible to carry out
the negotiation to reach an agreement.
Resource management . The resources are limited and once booked they
are no longer available, this is a further dimension that needs to be added
to the negotiation framework.
Distribution . The system runs in a distributed environment where the
user nodes are separate from the reservation server and possibly from the
The problem description for this application is presented in Table 20.1. It
defines the possible values and the available resources corresponding to
certain combinations of the possible values; the resource availability is
presented in Table 20.4, there are only certain computer types, that are
described by a certain combination of the values of the attributes CPU and